Rotary sprinkler



May 13, 1952 c. w. M BRIDE 2,596,577

ROTARY SPRINKLER Filed May 5, 1948 W Q. INVENTOR.

CLEEIEO w. CBRIDE:

ATTORNEY Patented May 13, 1952 UNITED STATES PATENT OFFICE ROTARYSPRINKLER Cleao W. McBride, Burley, Idaho Application May 5, 1948,Serial No. 25,220

1 Claim. 1

This invention relates to a rotary sprinkler suitable for watering lawnsor other areas.

The main object of the invention is to devise a rotary sprinkler forproducing a uniform distribution of water over the circular area coveredby the sprinkler. For this purpose, I have devised a sprinkler in whichthe amount of water supplied to the different portions of the circulararea is in proportion to the segmental area. In other words, the amountof water supplied to the outer portion of the circular area is greaterthan the amount of water supplied to the inner portion of the area.

Another feature of my sprinkler is a special arrangement of sprinklerarm with discharge apertures so arranged that the streams which issuefrom points of greatest discharge pressure cover the outer part of thecoverage area, and the inner part of the area is covered by streamsissuing at lower pressures.

A preferred embodiment of my invention is illustrated in theaccompanying drawing in which Figure 1 is a plan view of the sprinkler;

Figure 2 is a front elevational view of the sprinkler;

Figure 3 is an enlarged sectional view of the sprinkler taken along thecutting plane 3 -3 of Figure 2;

Figure 4 illustrates a step in the formation of the sprinkler arms; and

Figure 5 illustrates another step in the formation of these arms, bothfigures being on a reduced scale with respect to Figures 1 and 2.

Referring to the drawing, the sprinkler is provided with a suitable baseI on which is mounted a pipe elbow 2 having internal threads 2a in oneend thereof for receiving a hose connection and having the other leg 2barranged vertically. A short length of pipe 3 screwed into the elbow leg2b forms a tubular post or standard for supporting the sprinkler on thebase I. A cap 4 is threaded on the upper end of pipe 3 and is providedwith a tubular stem 4a forming a bearing for a threaded sleeve 5surrounding the stem. The sleeve 5 is provided at its lower end with aknurled ring portion 5a. A bearing ring 6 surrounds the stem 4a abovethe sleeve 5 and is held in position on the stem by an outwardly flaringend portion 4b on the stem which is formed after the sleeve 5 and ring 6are placed on the stem.

A rotary head 1 is secured to the sleeve 5 by internal threads formed inthe lower end 01 a vertical cylindrical cavity 1a formed in the head,

so that head 1 is mounted for rotation about the axis of the verticalstandard 3. The cavity la extends above the upper end of the bearingstem 4a and into a hexagonal portion of the head. Three tubularsprinkler arms 8, 8 and 8" each formed of a single linear tube extendradially from alternate faces of the hexagonal section of the head I andtheir inner ends communicate with the cavity la. These arms may besecured to the head 1 in any suitable manner, such as by soldering orwelding, but I prefer to mount the arms in the head by threadedconnections between the end of the arms and the head on horizontal axesas shown in Figure 3. A suitable locknut 8a (Figure 3) may be providedfor each arm to securely hold the arm in properly adjusted position. Theouter end of each arm is closed by a suitable plug 8!) threaded into theend of the arm so that it may be removed for cleaning out sediment whichmay accumulate in the arm.

The proper distribution of water by my sprinkler is secured by thespecial shape of the arms and by the special distribution of thedischarge openings in the arm. As illustrated by the arm 8 in Figure 2,each arm extends outward horizontally from the head i for about one-halfits length, and then it bends downwardly in generally a circular arcuntil the outer end of the arm is substantially in a vertical direction.Also, as shown in Figure 1 each arm extends radially outwardly from thehead I in a straight line for a short distance and then curves away fromits radial axis and in the direction of rotation of the head asindicated by the arrow 9 in Figure 1. The outer downwardly curvedportion of each arm is provided with a number of discharge aperturesformed in the outer wall of the arm, and these holes or apertures arespaced apart to provide a greater supply of water for the outer portionof the circular area covered by the sprinkler than for the innerportion. For example, in the specific embodiment shown in the drawing,seven discharge apertures are formed in the downwardly curved portion ofeach arm, and the streams of water proceeding from the apertures followgenerally the paths indicated by the dashed lines 8d. From these linesit will be seen that the holes adjacent the outer ends of the armssupply water to the inner portion of the coverage area, while the holesnearest the sprinkler head supply water to the outer portion of thecoverage area. Since the water pressure decreases along each arm towardsits outer end, the streams which are projected porting axes of" thearms. angular position of the arms, it is possibletovary from the pointsof greatest pressure are used to cover the outer portion of the coveragearea, and a larger coverage for a given pressure is obtained. To secureproper distribution of the water over the coverage area, the dischargeholes 80 are relatively widely spaced at the outer end of the arms anddecrease in spacing towards the head 7. This provides a greater densityof distribution of the discharge apertures in the region of the armwhichisupplies the outer portion of. the coverage area.

Since the sprinkler arms are all alike, at description of the formationof one arm will sufilce for all. The sprinkler arm is formed fromsastraight length of tubular stock, say 5 inches of A; inch tube. Thedischarge openingsyarexfirst bored in the tube while it isstillstraight,.,and a suitable distribution of the holes is secured if thefirst hole is located inch from the end, of the tube, and the other sixholes are provided with the following center to center spacing fromtheadjacent hole:-% i,-%fi;-e; /4",ii%",-1 6". A suitable size' for thedischarge 110165131 dia-meter. *After the holes have been-drilled in thetube, the two ,bendsmay bej-formed-in thetubein planes at right anglesto each other,'and the orderof forming the bends is not 9 important.--'1"he;outerend'of -the tube-may first be bent as shown in Figure 5 sothe discharge'apertures are positioned on theouter surfaee'ofzthe-arc,and

.then the other end of the. tube :may be bent in the 'planewatrightangles .to the. first bend, as

:shown in-Figure 4. If-desired, the bend shown inFigure 4 may be formedbefore the bend shown in'Ffigure 5.

The threaded connection between the: sprinkler arms-and the,rotary-head; permits the arms to be adjusted in angular positionaboutthe sup- By adjusting the the reaction force set up by thedischarge streams :and serving to rotate the sprinkler head. -It ispreferred to adjust the arms so that, the outer curved portions -of=;thearmsare tilted: somewhat with respect to the: verticalplane in' thedesired: direction of rotation of the? head, see armB" in "Figure 2. Thereaction force driving the rotary .head'is increased asthearms-aretilted :to a

greater anglewith respect-tothevertical. For

the purpose of preventing-the.streams fromone arm from following thesame circular pathszas "the streams of. anotherarm, the three arms may"be tilted to diiferent angles.

By .actual test.- I. have found. that any: sprinkler 10 "byway' oflimitation.

. gives substantially, uniform distribution oventhe 4 entire coveragearea. The extent of the circular area covered by the sprinkler isdetermined by the pressure of the water supply.

My invention is not limited to the specific embodiment described andillustrated herein, because it is obvious that any desired number ofsprinkler arms may be employed instead of the three illustrated in thedrawing. It will also be understood that the specific dimensions givenherein are for the purposeofillustration and not I claim: A rotarysprinkler comprising a rotary head mounted for rotation on a verticalaxis and having a plurality of tubular sprinkler arms mounted thereon,each of said arms comprising a single linear tube having one end thereofclosed and the other end thereof being secured to said head.onahorizontal axis extending radially from said head, the outer endportion of each arm being curved generally downwardly insubstantially a,

circular'areofsubstantially and having a plurality: of dischargeapertures formed in the outer wall of said curved portion and spacedalong thelength thereof by a spacing-which decreases progressively fromthe outer end of. the arm toward the rotary head, the-apertures nearestthe-end of each arm being .directed to supply :Water to theinnerportion-ofthe coverage area and the I apertures :nearest .thesprinkler head being directed to supply water to .the outer por- -tionofthe-coverage area.

CLEAO 1W1 MCBRIDE;

.BEFERENCES ..CITED The." following: references are of record :in-- thefile ofthis patent:

UNITED STATES: PATENTS ;I.Germany Jan, 22, 1931

